Wave machine



Oct 6, 1931. p, E, KLQPSTEG 1,825,739 WAVE MACHINE Filed May 16. 1929 "5 gation' of energy through ther mediumof ticles. l 55 waves has, so far as I am aware, been very e The preferred embodiment of the inveninadequately met. To be sure, wave mation is illustrated lin the accompanying chines have Vbeen described in technical lit-v drawings, in which y erature and some'of them have been made Fig. lis a diagrammatical side elevation;

VI0 available to the trade. Fig.'2 is a side elevation with the inter- 60 `For example, there was one known as the mediate portions broken away;

Columbia wave machine :with which arti- Figs. 3 and l are plan viewsshowing the icial transverse, longitudinal and water pendulums arranged in dilierentpositions; waves could be demonstrated. $.13. Thomp- Fign'is a yplan view orP an instrument 1,5 son devised a wave apparatus to give a clear used to 'adjust the elastic connections be- 65 `20 transmission and reception. Weinhold dedemonstrations. 70

i" '2,5 Perhaps the only other wave machine of the beam 10 is a column composed of bars 75 *T30 a very Serious drawback ih Jhat the Waves ed perforations into which bushings 16 are '80 u 35 wave troughs for demonstrating water t0 IGCeVe and Support vthe short bar 21, '85

*745 such complete adaptability as to eliminate right column, and when' those axes are in 95 Patented Oct. 6, 1931 n y* i UNrrEDl STATES A Parulazlvl",A oFFlc-s Applicatonrled May 16,1929.y Serial No. 863,'6-89.

The well recognized need lwhich has long transverse, or vice versa, at will, and thereexisted for apparatus capable of demonby conclusively show rthat the difference bestrating all or nearly all the different as# tween the two wave types is merely one of pects of wave motion including the proparelative direction of' oscillation of the parideal of `the propagation of energy Yin an tween the pendulums, and i v elastic'medium throught the agency of-trans- Fig. 6 is a perspective view of a weight or verse Waves', the apparatus,` being intended l mass suitable yfor use in connection with a for objective representation of wireless wave one or more of the pendulums in certain scribes a machine which, though very large The base of the machine includes a chanand cumbersome, may be used to flemon'- nel bar l0, having a CIOSS piece l1 at its ellClS strate actual longitudinal waves with each fitted with a pair'of level screws 12 great elearness and beauty. which serve as feet.l Rising from each end Worthy of mention is that of Mach 'which 13, having their upper endssecured to the enables one to produce artiiicial waves, ClOWlltulIled flanges 14 0f a top channel bar either longitudinal or transverse, and either l5- v Y progressing or Standing, It, howevera had Theweb of this barhas a series of threadwere merely simulated by the balls of bifilar fitted ECh bushing SQFVGS 3S belligs pendulums, andy any idea of an elasticV mefor a short shaft 17,*orm1ng the shank'of a dium had to be supplied subjectively in the qk Kthe-m1311819, of Which are equipped students mind. There have been, of course, withv adjustable pivot bearings 20, adapted waves, but they are of no particular interest OIIIlIlg the upper',` end bf e Pendulum 22. Yin this connection. o The shafts `are held l1n place by suitable 'i A Wave machine ,is necessarily con.. 1111135 23 WhlCll hLVe/ille Side allges 24 IQS- vsiderable proportion and, because of *thel .111g 0n the UPPGI ends Ofthe bllShIlgS l6 ket,"its production' is relatively costly.y It arm 25, `all of which are pivotally connected is, therefore, the principal object of this in- CO e bal' 26 0f SllCll length that When the vention to produce a machine that will be rilXeS O'fthe pendulums areV 1n one extreme inexpensive to manufacture and will have position the right end of the bar strikes the the necessity of supplying more thanone another extreme position the opposite end type of machine to a single institution.` The of the bar strikes the oppositeV column 13, presentinvention permits a'mechanical arthe two positions being illustrated in Figs. rangement enabling the demonstrator to 3 and 4. i

501change thewave type :from longitudinal to yOne of the nuts 23 is extended and pro- 100 vided with a knob 27 forming a handle by which the several pendulums may be rotated to change their positions simultaneously.

Each pendulum 20 is equipped with a friction collar 28 having a deep groove 29, and adjacent pendulums are fiexibly nected by rubber bands 30 looped about the collars and seated in the grooves.

Two rods 32 are fixed to the webs of the channels V10 and 15 at a distance from the end pendulums corresponding to Vthe space between the several pendulums, and each rod is fitted with a collar 2S, having a groove 29, like those on the pendulums. The collars may be simultaneously and uniformly adjusted with the aid of a notched bar 33, shown in F 5.

The parts 30 introduce elasticity into the medium represented by the several pendulums, and make it possible to produce actual as distinguished from artificial Waves. When all the collars are at the same height there is uniform elasticity which is increased by moving them downwardly, and decreased by moving them upwardly.

The use of ordinary rubber bands between slidin collars or pendulums makes if possible to o tain this elasticity without interfering with the mechanism for turning the pendulums from one position to another. Introducing the elastic connection between an end pendulum and a fixed rod 32 has the effect of introducing a "dense medium at the end of the series of pendulums.

JWith the collars about half way down the pendulum rods, t-ransverse or longitudinal, pro rressing, 0r standing waves may be produce with the greatest facility. Displacing an end pendulum a suitable amount starts a progressing wave, displacing an end pendulum suddenly either outwardly or inwardly, roduces rarefactions and condensations. Siimultaneously releasing end pendulunas after equal displacement in opposite directions produce a beautiful illustration of destructive interference, the middle pendulum, or particle, receiving the progressing impulses from opposite directions remains stationary. If, on the other hand, liendulums are displaced in the same direction the impulses reach the medium particle simultaneously, and are additive, which results in its having a very large amplitude.

Two slotted masses 34 (Fig. 6) are provided for application to the end pendulmns, as indicated 1n dotted lines in Fig. 2, to give them greater energy and vibration when it is desired to demonstrate the S. P. Thompson experiment to illustrate the transmission and reception of energ through wave motion. In this instance t e collars 28 should be about one-third of the distance from the top of the pendulums.

Displacing one of the end pendulums 3 causes a wave to travel slowly to the other end of the series and after some seconds a series of equally timed impulses reaches the other end pendulum and it is set swinging with an amplitude not appreciably less than the first or transmitting pendulum.

These suggestions will be sufficient to illustrate the possible demonstrations and those familiar with wave motions will readily adopt others producing the desired effect.

In order to make the demonstrations coinpletely objective, and leave practically nothing to the imagination of the student, the lower ends of the pendulums` are fitted with balls 31, representing particles whose wave motions are to be studied.

In the preferred commercial embodiment of the invention the pendulum rods 22 are made of light aluminum alloy, the bars 21 have hardened cones receiving the ivot bearings, the forks 18 are castings, the )usbings 16 are bronze, and the frame is composed of commercial sections. Consequently, the device is very rugged, very slmple to manufacture, and requires a minimum of attention to maintain.

The rods are painted or enameled black and the balls painted white or plated with bright metal to obscure the rods andmake the balls more conspicuous.

I claim as my invention:

l. In a device of the class described, a horizontal beam, a plurality of vertical shafts journalcd in the beam in a row, a pendulum mounted on each shaft, and including a rod and an adjustable collar thereon, an elastic connection between adjacent pendulums associated with said collars, and means to rotate the several shafts and retain the axis of the pendulums in a selected relative position.

2. In a device of the class described, a horizontal beam, a plurality of vertical shafts journaled in the beam in a row, a pendulum carried by each shaft and including a slender rod of light material, a weight` attached to the lower end of the rod and a collar adjustable along the rod above the weight, an elastic connection between the collars of adjacent pendulums, and means for rotating the shafts in unison and retaining them in a selected relative position.

3. In a device of the class described, a horizontal beam, a plurality of vertical shaft-s journaled in the beam in a row,` a pendulum mounted on each shaft, an elastic connection between adjacent pendulums adjustable vertically with respect thereto, and means to rotate the several shafts in unison and hold them in a selected relative position.

4. In a device of the class described, a series of pendulum forks, each mounted to rotate about a vertical axis, a pendulum mounted in each fork, an elastic connection between adjacent pendulums, and means for rotating the forks in unison and retaining the axes of the several pendulums in a selected relative position.

5. In a device of the class described, a series of pendulums in a row, means to mount the pendulums to swing about hori-k zontal aXes on a level, and to rotate on vertical axes, and an elastic connection between adjacent pendulums.

6. In a device of the class described, a series of pendulum forks, each mounted to rotate about a vertical axis, a pendulum mounted in each fork, an elastic connection between adjacent pendulums, and means for rotating the forks in unison and retaining the axes of the several pendulums in a selected relative position.

7. In a device of the class described, a series of pendulums, in a row, means to mount the pendulums to swing about horizontal axes on a level, and to rotate on vertical axes, an elastic connection between adjacent pendulums, and means for rotating the pendulums simultaneously and revhorizontal beam, a series of weights suspended from the beam by rigid pendulum arms, means associated with the beam causing the pendulums to oscillate in parallel planes and means for varying the angularity of the parallel planes with respect to the beam.

In testimony whereof I aiX my signature.

l PAUL E. KLOPSTEG. 

